A bearing arrangement of this type of a wheel hub of a motor vehicle drivable by a rotating joint is known from DE 42 10 461 C2. In the case of this arrangement, the non-rotatable connection of the wheel hub and rotating joint is facilitated by a threaded journal having a shaft serration which engages with a appropriately configured axial inner serration in the axle stub of the wheel hub. The counter-surface of the joint body of the joint shaft acts in a twofold manner on the bearing inner ring protruding beyond the axle stub of the wheel hub, namely as a result of the fact that an end side of the counter-surface presses onto an end side of the axially protruding bearing inner ring and as a result of the fact that an axial surface of the counter-surface supports the protruding part of the bearing inner ring. The aim of this arrangement is to prevent deformation effects, in particular deformation effects of the type which act on the bearing inner ring as a consequence of bending moments.
An advantage of an arrangement of this type is a relatively compact and short construction of the wheel hub/rotating joint unit, as at least some of the joint body is received axially in the wheel hub. An increasingly desirable shift of the joint shaft center point from the outer ball joint as far as possible in the direction of the vehicle exterior therefore takes place. However, the configuration of the serration as a shaft serration must be regarded as a drawback, as with such substantially axially extending serration the setting of the correct spacing of the components from one another appears problematic. Furthermore, the counter-surface of the joint body acting on the end side of the bearing inner ring makes precise setting of the necessary prestress of the bearing inner ring difficult, as bracing of the wheel bearing unit to the joint shaft gives rise to the problem of the overdetermination for the desired axial freedom of play of the serration and wheel bearing air by way of two axial or radial abutment points in the region of the abutment of the joint shaft against the bearing inner ring.
Other bearing arrangements of a wheel hub of a motor vehicle drivable by a rotating joint are known. These arrangements do not have these problems but are capable of improvement in other respects.
DE 31 16 720 C1 discloses a bearing arrangement in which the entire inner ring is formed in one piece on the wheel hub, so that the setting of the prestress and the fixing of a separate bearing inner ring are immaterial there. An end serration, which corresponds to an end serration in the joint outer part of the joint body, is formed into the end side, directed toward the joint body, of the axle stub of the wheel hub, thus ensuring a simple, releasable fastening of these components. An arrangement of this type is not suitable for bearing arrangements comprising multipart inner rings. Although this configuration is to afford a low axial overall length, this length is still too great for current-day demands for increasingly compact vehicles with less and less available installation space.
A similar arrangement is known from DE 36 04 630 C2 in which the axially terminal end serrations of the wheel hub and rotating joint are pressed in an oscillating manner. This arrangement also takes up a relatively large amount of axial installation space.
DE 36 36 243 C2 discloses a wheel bearing/constant velocity joint unit comprising a double-row bearing comprising at least one bearing inner ring which is formed separately from the wheel hub and is axially held or braced by a reshaped collar formed on the wheel hub. The collar can in this case be provided directly or indirectly via an intermediate part for mounting the bearing inner ring. The reshaping method used is in particular cold reshaping. In the case of one embodiment of said document, provision is made for an end or oblique serration to be formed into the reshaped collar, which radially outwardly overlaps the bearing inner ring, of the wheel hub, wherein the end or oblique serration can be directly, non-rotatably connected to a joint component, in particular the joint outer part. A configuration of this type is to allow an extensive, radially oriented end serration or slightly conical oblique serration to be provided independently of the type of bearing configuration, wherein according to a appropriate method the oblique or end serration is impressed into the material at the same time during manufacture of the collar.
In the case of DE 36 36 243 C2, another configuration provides for the formation of an oblique or end serration on an annular projection which radially outwardly increases the size of the bearing inner ring, wherein the end or oblique serration can be directly, non-rotatably connected to a joint component, in particular the joint outer part, and in which the bearing inner ring comprises engagement means with which the reshaped collar engages in a form-fitting manner. According to this, the separate bearing inner ring, which can be provided with an enlarged end face, takes part in the transmission of torque from the hub to the rotating joint.
In the case of this solution, an axial serration is applied to a roller-riveted collar by material reshaping. This roller-riveted collar with serration requires additional installation space in the axial direction. This causes an increase in the size of the bending angle of the joint shaft and thus has a negative influence on the service life of the joint shaft and the steering lock of the vehicle.
Finally, U.S. Pat. No. 6,146,022 discloses a bearing arrangement of a wheel hub of a motor vehicle drivable by a rotating joint, which is in itself very advantageous with regard to a low installation length. The axle stub of the wheel hub and an end side of the joint body have mutually corresponding end serrations, the end serrations being disposed roughly centrally below the raceways of the bearing arrangement. In this case, one inner raceway is formed in the wheel hub and the other inner raceway in the jacket of the joint body. As a result of the integration of the rolling body raceway into the joint body, the installation space required axially is reduced. The center point of the joint body therefore migrates further in the direction of the vehicle exterior. Nevertheless, in the case of an arrangement of this type, the necessary prestress of the rolling bodies of the bearing arrangement is difficult to set.